Geoege gumming



(No Model.)

; G.- GUMMING. RIVETING MACHINE.

-1 T0..244,437. Patented July 19,1881.

UNITED STATES PATENT OFFICE.

GEORGE GUMMING, OF SAN FRANCISCO, CALIFORNIA.

RIVETING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 244,437, dated July 19, 1881.

Application filed March 12, 1881. (No model.)

To all whom it may concern justable steam or hydraulic cylinder or other power cylinder so connected with the arm or lever by which the riveting is done that the pressure may be varied, and the power accommodated to different kinds of work.

It further consists in a means for lengthening or shortening the-pipefor conveying steam or water to the cylinder, whereby the'connection may be preserved upon moving the cylinder.

It consists, also, in a peculiar form of packing, both for the joints of the adjustable pipe and for the piston. All of this will hereinafter more fully appear. 7

Referring to the accompanying drawings, Figure 1 is a longitudinal section. Fig. 2 is a transverse section. Figs. 3 and 4: are details of construction.

In riveting-machines the difficulty has been to regulate the pressure for different work and different-sized rivets. The pressure is at present applied directly upon the rivets, and is the same for all kinds of work. Its results are often not satisfactory, for a great pressure applied toasmall rivetfor thin sheets will press the rivet out of shape and dent and otherwise injure or deface the material to be riveted.

My invention has for its chief object the regulating of the pressure applied to the movable jaw, so that by the use of the same power applied at a different portion of the machine the power of the movable jaw can be regulated for different work.

Let A represent a frame supporting the upright stationary arm or jaw B. 0 represents the movable jaw, constructed in the shape of a bell-crank lever, pivoted at a 011 the frame A. The upper inner ends of both jaws are provided with the projecting dies b. The horizontal arm of the movable jaw 0 projects between the frame, as shown. Under this arm of the movable jaw is the cylinder D, with its arm of the movable jaw. This is done, as

piston E, upon which the arm of the jaw Q rests, or with which it may be connected.

I have here shown the power applied by means of a hydraulic-pressure cylinder. Water is supplied to the cylinder through the bent pipe F, leading from the valve Gr, connected with the ram. The cylinder D is arranged to be adjusted under any part of the projecting here shown, by having the frame A divided and hanging the cylinder D between it, supporting it by a flange at its top. It can thus he slipped along the frame, or it might beset on guides or fixed in any practicable way. 6

It will be seen that the pressure of the piston E upon the extreme end of the arm will exert a greater pressure upon the upper end of the movable jaw C than when moved up nearer the pivot-point. Thus, by moving the cylinder, the leverage can be lengthened or shortened, and the power of the machine regulated.

In order to allow the cylinder to be moved back and forth, the connecting-pipe F must be extended in some way. When steam is used this pipe could be severed, and one end provided with a stuffing-box, which would allow the other to slip in or out to the desired length but in case water is used, I deem the construction here shown more practicable. The pipe F is composed of a number of short vertical and horizontal pieces, the ends of which are provided with screw-threads and screw into common gas-pipe elbows, thus joining them together in a series of bent sections, as shown. It will be seen'that this construction will allow the pipe to be extended by the turning of any of the jointed pieces. In the use of water under such great pressure as is here required, it is necessary to have very thorough packing at the joints.

In the pipe F, I have packed the joints as follows: In the screw-threads on the ends of the sectional pipe I cutout a few threads, leav- 9 5 ing a smooth depressed surface or groove around the pipe near the end, as shown in Fig.

3. In this groove I place hemp or other flexible packing. When the water is forced through it has the effect of pressing out or bulging this 100 layer of packing and making it fit tightly the surrounding pipe. It is held well in place by the screw-threads, and will not interfere with. the turning of the pipes. Thus the ends of the pipes may be screwed into the elbows and a perfectly movable joint made, which will be thoroughly water-tight. I follow out the same principle in the piston E. Around its lower part I cutout the groove (1. The hempor other flexible packing is fitted into this groove, and the great pressure of water upon the lower end of the piston forces some of it in behind and below the packing, thus causing the latter to be fitted closely into the cylinder and make a water-tight joint. In order to prevent this flexible packing being forced out of its groove into the space between the cylinder and the piston, the upper part of the groove has an angular concave form, as shown at c, this angle making a sort of a hooked edge all around the upper part of the groove, which holds the packing in place and prevents it being forced out of the groove. This form of packing takes the place of cup-leathers, which are ordinarily used for hydraulic pistons, and will not wear as rapidly or need repairing as often as the cup-leathers.

Having thus described my invention, what I claim new, and desire to secure by Letters Patent, is-

1. In combination with a riveting-machine havinga stationaryandamovable jaw with pro- 0 jecting riveting-dies, as shown, the pressurecylinder D, with its direct-acting piston E, said cylinder being capable of adjustment, so as to vary the pressure upon the movable jaw, substantially as and for the purpose herein described.

2. In a riveting-machine composed of the stationary jawB and the movable jawG journaled in the frame A, as shown, the cylinder D, with its piston E, constructed to act upon the movable jaw C so as to produce a varying pressure upon the riveting-dies, and the bent sectional pipe F, connected with the cylinder and its source of supply, whereby the adjustment of the cylinder may be made and the pressure regulated substantially as described.

3. The bentsectionalconnecting-pipeF, uniting the hydraulic cylinder D with its source of supply, said pipe consisting of the short vertical and horizontal lengths screwed loosely into connecting-elbows, and having grooves turned in their threaded portion to receive a hemp or other flexible packing, which is forced into the interior threads of the couplin gby the water-pressure, whereby a perfectly-tight and easily movable jointis provided, substantially as described.

4. The piston E, adapted to move within the hydraulic cylinder D under pressure of a column of water, said piston having the groove (1, with its angular or concaved upper flanges, e, whereby the packing is forced outward by the pressure of the water to form a tight joint and is prevented from being crowded between the piston and the cylinder, so as to bind, substantially as described.

In witness whereof I have hereunto set my hand.

GEORGE CUMMING. Witnesses:

S. H. NoURsE, FRANK A. BRooKs. 

